Vtech child laptop programming

[Brynet-Inc]

I expect the processor to be that black dot in the middle where all the lines are going.

Nice catch, I barely noticed that little epoxy covered blob in the picture...

@djtrickdog, Assuming the ROM wasn't exposed to much UV light.. it might be possible to determine the architecture by analyzing it's contents as Combuster mentioned.

But it's probably more work then it's worth though... desoldering it.. etc..

[djtrickdog]

http://www.bash.org/?834654

That's an EPROM. Electronically programmable ROM. You shine a UV light through the hole to reset the ROM so it can be programmed again. That's why it was covered with tape...

wow thats pretty useful especially since i want to reprogram. I took the tape off at night so no sunlight got to it, i hope my light bulbs aren't UV

I expect the processor to be that black dot in the middle where all the lines are going.

In other words: processor type unknown. You could try to dump the rom and figure what architecture of assembly's in there, but it'll be hard to give a definite answer

Dang i saw that before but i didn't think it was useful :/. Nice catch. In order to dump the rom, could i do with without pulling it off the motherboard?

@djtrickdog, Assuming the ROM wasn't exposed to much UV light.. it might be possible to determine the architecture by analyzing it's contents as Combuster mentioned.

But it's probably more work then it's worth though... desoldering it.. etc.. Wink

It wasn't i assume either. As far as the work not worth it, hey i have nothing else to do. But if i can dump without desoldering, that would be awesome

Anyone wanna hit me up a tutorial on Dumping rom chips? This is a first timer for me and if i HAVE to pull it, id like tutorial on that too.

[earlz]

wow...this is probably the coolest topic I've read in a while...makes me wish I could do stuff with electronics...

[bnitz]

I was given a broken one of these toy laptops which mysteriously started working again when my toddler drooled on it.
Based on a search through google groups on:
Whiz Kid vtech motorola

It looks to be based on a Motorola 6805. It's quite a nice processor for its time, it may have been necessary to have a full fledged 8-bit CPU in order to playback the digitized voice, though I suppose a less powerful microcontroller could do it with some custom support chips. Anyway, it should be possible to reprogram by someone with much more time than I have and the ability to:

- Carefully unsolder the EEPROM, install a socket (zif would be best!)
- Read the EEPROM, try to find the OS address space and disassemble to try to figure out how the hardware is addressed (LCD display, audio output, keyboard scan...)
-Write your own operating system which does something useful with the same hardware.
- Burn and insert the new EEPROM
- Try to sell the EEPROM to the handful of others who still own this device and are unsure of what to do with it.

Or hire the guy who helped develop the thing. I'd like to see it speak the words typed (it already speaks pre-canned words and characters), but I suspect the address space was too tight for much of a text/speech dictionary. If you could get that working and use the fake ethernet or printer port to access a device with an ocr chip on it, you might be able to make some sort of reading device.

Even though this device may have been the last generation of toy laptops which are relatively easy to modify, there are far more C64s and older computers which are much more fun and popular to hack. I'd love to know enough about the hasbro ION game system (with built in camera and Gesturetek motion sensing) to be able to write new software for it since hasbro only released a handful of mediocre games, but it's not a very open system.

[jal]

I was given a broken one of these toy laptops which mysteriously started working again when my toddler drooled on it.

You do realize that you are ressurecting a 1.5 year old thread, right? :) Slightly more OT, I wish there was a home brew scene for their slightly more advanced products, like the vtech vsmile, pocket, motion, etc. They're based on ARM, so it should be possible to create some stuff for it...


JAL